BeckhoffKL30022-Channel Differential Analog Input Bus Terminal, -10 to +10 V, 12 Bit, 12 mm, DIN Rail

Product Description

What this part is

A Beckhoff KL3002 analog input Bus Terminal — a 12 mm wide DIN-rail I/O slice that adds two differential voltage inputs to a Beckhoff K-bus station. It digitises a bipolar −10 V to +10 V signal at 12-bit resolution and hands the value to the fieldbus through the bus coupler at the head of the terminal block.

Decoding the designation

KL – Beckhoff Bus Terminal on the K-bus (as distinct from EL terminals, which run on EtherCAT)3 – analog input group0 – voltage input02 – two channels, ±10 V range

What these specs mean in practice

Differential inputs are the reason to pick this terminal over a single-ended one: each channel measures the difference between its own pair of terminals, so common-mode noise picked up on a long signal run largely cancels. The channels do, however, share a common internal ground potential, so they are differential but not mutually isolated — do not treat the two channels as galvanically separate circuits. The 500 V isolation figure applies between the field side and the K-bus, which is what protects the controller. And because the range is bipolar ±10 V, 12 bits are spread across 20 V, not 10, so the effective step size is about 4.9 mV; if you need finer resolution on a unipolar 0 to 10 V signal, a higher-resolution terminal is the better choice.

Published specifications

Function: analog input, voltageChannels: 2, differentialSignal range: −10 V to +10 V (bipolar)Resolution: 12 bitCommon ground: channels share an internal ground potentialGalvanic isolation: 500 V, field side to K-busCurrent consumption: 65 mAHousing width: 12 mmMounting: 35 mm DIN rail, Beckhoff Bus Terminal systemOperating temperature: −25 to +60 °C

Quantity and configuration

Sold as 1 piece — the terminal only. A KL-series terminal cannot work alone: it needs a Beckhoff bus coupler (BK or BC series for the relevant fieldbus) or a bus terminal controller at the head of the station, plus a KL9010 end terminal to close the K-bus. None of those are included, and no connector or shield accessory is supplied.

Installation and setup notes

Wire each channel as a pair — signal and its own reference — rather than tying returns to a shared 0 V, or the differential benefit is thrown away. Run the signal in screened cable with the screen landed at one end only. Terminal order matters for the process image: the coupler numbers analog terminals in the physical sequence they occupy on the rail, so inserting or moving a terminal shifts the addresses of everything downstream.

Interchange guidance

KL3002 and KL3402 are both two-channel ±10 V terminals but are not the same part; KL3012 and KL3022 are the 0/4 to 20 mA current-input equivalents and will not read a voltage signal. KL3202 is a resistance-sensor (RTD) input despite the similar number. The EL3002 is the EtherCAT terminal with the same signal specification — it is the modern counterpart but runs on a different bus and will not work behind a K-bus coupler. Within the KL range, mixing terminals is normal; mixing KL and EL terminals in one station is not.